Healthy development of children involves successful coping with stressful experiences. Complex and important relationships between stress and illness have been studied in adults. The presence and emergence of these relationships in the context of the family and the developing child have not been extensively studied. The proposed research examines relationships among stress, illness, coping, and health through a cross-sectional and longitudinal study of 200 school aged children and their families. Half the children will be composed of "normative" sample drawn from intact families without mental health problems. The second half will be a "high stress" sample drawn from families undergoing a higher level of stressful experiences associated with a marital separation within the two year period prior to study entry. A developmentally informed taxonomy of stress and coping is to be generated and form the basis for subsequent examination of the health status of the children and families. The moderating influences of social support, cognitive style, temperament and sociodemographics will be examined. Over a three year period, four groups of children will be studied with measurements at study entry, one year follow-up and two year follow-up. Both the normative and high stress groups will be composed of 50 children age 6 years at time of study entry and 50 children age 9 years at time of study entry. Longitudinal assessment of these cross-sectional cohorts will yield measures for children ages 6, 7, 8 and 9, 10, 11 years. The measures administered in home visits assess stress and coping as experienced by the children and their families; moderator variables such as cognitive style, social support, temperament, and sociodemographics; and health status indicators such as behavior symptoms and social competence. An additional set of health indicators is gathered for each family from their medical records at the Health Plan. Data analyses seek to describe relationships among stress, coping, health and illness in terms of age differences and stress group diferences. It is expected that the research will contribute to our understanding of these relationships and processes and help guide the development of clinical interventions for promoting and maintaining health.